Here, we report some of the results recently presented in
Ref. [1]}, to which we refer for further details.
The aim of our work is to study — in a model-independent
way — the analytic structure of the four-dimensional SU(2) (quenched)
Landau-gauge gluon and ghost propagators in the IR regime, by
using rational approximants as fitting functions to the data from
Refs. [2]}, [3]}, [4]}. We note that rational approximants were
recently applied by Falcão, Oliveira and
Silva [5]}, [6]} to analyze the Landau-gauge
gluon and ghost propagators in the SU(3) case. We stress, however, that
in Refs. [5]}, [6]} the issues related to
error propagation, and in particular the uncertainties arising from the fit
procedure, are not
fully discussed. In this work we propagated all the errors, considering
off-diagonal correlations when necessary. As shown in
Ref. [1]}, this limits considerably the number of
parameters that can be determined from our fits.
